<!DOCTYPE HTML>
<html>
<head>
<meta charset="utf-8">
<title>无标题文档</title>
<style>
div {width:100px; height:50px; background:red; margin:10px;}
</style>
<script>
window.onload=function ()
{
	var aDiv=document.getElementsByTagName('div');
	
	for(var i=0;i<aDiv.length;i++)
	{
		aDiv[i].onmouseover=function ()
		{
			startMove(this, 400);
		};
		
		aDiv[i].onmouseout=function ()
		{
			startMove(this, 100);
		};
	}
};

var timer=null;

function startMove(obj, iTarget)
{
	clearInterval(timer);
	timer=setInterval(function (){
		var speed=(iTarget-obj.offsetWidth)/6;
		speed=speed>0?Math.ceil(speed):Math.floor(speed);
		
		if(obj.offsetWidth==iTarget)
		{
			clearInterval(timer);
		}
		else
		{
			obj.style.width=obj.offsetWidth+speed+'px';
		}
	}, 30);
}
</script>
</head>

<body>
<div></div>
<div></div>
<div></div>
</body>
</html>
